define(function () {
  function isEmpty(input) {
    return input == null || input == '';
  }

  function isBlank(input) {
    return input == null || /^\s*$/.test(input);
  }

  function startsWith(input, prefix) {
    return input.indexOf(prefix) === 0;
  }

  function endsWith(input, suffix) {
    var regex = new RegExp(this.escapeMetacharacterOfStr(suffix) + "$");
    return regex.test(input);
  }

  function contains(input, searchSeq) {
    return input.indexOf(searchSeq) >= 0;
  }
  return {
    isEmpty: isEmpty,
    isBlank: isBlank,
    startsWith: startsWith,
    endsWith: endsWith,
    contains: contains
  }
});